Performs routine fuel system maintenance, valve packing replacement, valve replacement, pump repairs, pump overhauls, electrical troubleshooting and repair, instrumentation calibration and troubleshooting) and complex (equipment alignment, continuous emissions monitoring systems, distributed control systems, turbine overhauls) maintenance work, as assigned. Controls, monitors, and evaluates plant production equipment and output including efficiency and related variables (e.g., heat rate, cost/unit of production, system demands, and capabilities given various circumstances) and the overall effectiveness of operation practices and procedures.